Geochemical Characterization of Serpentinized Peridotites from the Shergol Ophiolitic Slice along the Indus Suture Zone (ISZ), Ladakh Himalaya, India

摘要

The Shergol ophiolitic slice is a dismembered ophiolite consisting predominantly of serpentinized peridotites along the Indus Suture Zone, Ladakh Himalaya, India. On the basis of modal mineralogy, Shergol serpentinized peridotites can be identified as spinel-bearing harzburgites. The characteristic U-shaped rare earth element (REE) patterns and whole-rock heavy-REE concentrations correspond to those of abyssal mantle rocks from mid-ocean ridges. Evaluation of Cr-spinel mineral chemistry reveals that they represent the residues left after low-to-moderate degrees of partial melting (<15) in the spinel stability field in a mid-oceanic ridge tectonic environment. The whole-rock geochemistry suggests that the studied rocks represent a mantle residue left after removal of basaltic melts in the context of an ancient Jurassic-Cretaceous Neo-Tethys oceanic mantle section.